A classic piece of vintage audio on my workbench - Siera 5521 / Philips 22RH521 - Part 1
ฝัง
- เผยแพร่เมื่อ 24 ก.ค. 2024
- I have a wonderful piece of vintage audio equipment on my workbench this time, the 1973 Siera 5521 Stereo Amplifier. It is identical to the classic Philips 22RH521, also dubbed the "fisheye amplifier", which gained some of a cult following for its looks and sound.
In this video we get a first look of the patient, examine the inside and diagnose the first issues which we need to tackle.
WARNING: Do not attempt to repair electronic equipment if you don't know what you're doing.
If you enjoy my content, consider buying me a coffee:
www.buymeacoffee.com/retrotech
Music by Karl Casey @ White Bat Audio
Noise video footage by Milan Matos
Electrocution logo by Nesdon Booth, The Noun Project - วิทยาศาสตร์และเทคโนโลยี
That's great Receiver keep up good work
I Recently bought a Philips 22AH561 its pretty much same Amplifier, only difference it's the VU meters are fisheye type amazing sound, thank you for your Videos they are going to be helpful in case i need to repair mine, just subscribed
Thanks!
fantastic bit of kit 👌 spot on
What a nicely laid out unit.
It seems the European look in the 70's was different to the Australian look. We had some wooden case units, but I remember mainly silver faced stereo equipment.
I think we were very influenced by the Asian market back then as they were geographically closer for shipping gear to Australia
Lamps are in series, and they have to be of 6V, 50 mA type. Idle current of this amp is huge, 400 mA per channel, so we can say it is a class A amplifier for home listening levels. I love the way it sounds.
Correct. I was planning to talk about this in the next video.
I would have started with the PowerSupply and got that rebuilt (if necessary, those Philips caps usually are fine).
Then cleaned the switches and replaced the bulbs (bet their in series, and only 1 is blown).
Usually I hate working on Philips equipment, those old brown PCB are so easy to lift traces from, and those thin stiff wires, all in the same color...
But this unit looks better constructed, but still unmistakably a Philips 😊
Good luck with your project, looking forward to the next part.
Well, in this case I will first fix the blown output before I do anything else. Then I'll move back to servicing power supply and amp. The caps are indeed still fine but I will probably replace them anyway as I want them still to last many years.
STEREO 4 is not just Speakers A and B together. By this setting, the back speakers reproduce the difference between left and right signal, giving a kind of Hall effect.
I had a better look at the schematic and indeed you're right. I spoke a bit too soon. Apparently I have to apologize to Philips... AGAIN... ;-)
Pseudo-complementary class AB if I’m not mistaken. First one one I’ve seen in the wild.
Don sent me. Looking forward to the video.
Glad to hear! Hope you enjoy my channel.
Aristona definitely was slightly cheaper than Philips. Never heard of Sierra but I do know Erres as a Philips product, in the same category as Aristona.
Nice to see it was designed with serviceability in mind. They certainly knew how to design and build things in Eindhoven.
I think Siera was more oriented to the Belgian market, since it was originally registered as a Belgian company and as a result the brand was more known over here.
Isn't the TO3 insulator mica? Would be period.
Indeed, I misspoke.